Benchmark: String from Charcode cached (deg)

Script Preparation code:

var chars = [239,15,2,1,227,15,118,2,68,63,49,59,56,90,0,44,15,143,1,206,15,251,7,255,56,15,43,2,206,15,225,0,255,74,15,135,3,255,56,15,74,1,71,15,0,3,255,74,15,92,1,242,15,172,8,44,15,63,0,107,15,194,1,242,15,5,1,224,15,118,2,65,15,184,11,255,17,63,49,59,56,234,6,71,15,90,0,218,15,180,3,224,15,243,0,255,56,15,42,3,218,15,237,0,161,15,235,2,255,56,15,74,1,255,8,15,3,9,65,15,84,0,86,15,215];

Tests:

For-loop
var s = ""; for(var i=0,l=chars.length; i<l; i++) s += String.fromCharCode(chars[i]);
String.fromCharCode.apply
var s = String.fromCharCode.apply(null, chars);
loop: String cached
var s = ""; var S = String; for(var i=0,l=chars.length; i<l; i++) s += S.fromCharCode(chars[i]);
loop: String.fromCharCode cached
var s = ""; var f = String.fromCharCode; for(var i=0,l=chars.length; i<l; i++) s += f(chars[i]);
join: String.fromCharCode cached
var s = new Array(chars.length); var f = String.fromCharCode; for(var i=0,l=chars.length; i<l; i++) s[i] = f(chars[i]); s = s.join('');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
For-loop
String.fromCharCode.apply
loop: String cached
loop: String.fromCharCode cached
join: String.fromCharCode cached

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 months ago)

User agent: Mozilla/5.0 (Windows NT 5.1; rv:52.0) Gecko/20100101 Firefox/52.0

Browser/OS: Firefox 52 on Windows XP

View result in a separate tab

Test name	Executions per second
For-loop	197931.9 Ops/sec
String.fromCharCode.apply	539508.3 Ops/sec
loop: String cached	237576.6 Ops/sec
loop: String.fromCharCode cached	242205.9 Ops/sec
join: String.fromCharCode cached	214051.4 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 2 months ago):

LLMs can make mistakes. Check important info.

Measuring performance differences in JavaScript microbenchmarks can be fascinating and useful for developers.

**Benchmark Overview**

The provided benchmark measures the time it takes to concatenate characters from an array into a string using different approaches: `for` loop, `String.fromCharCode.apply`, `loop: String cached`, `loop: String.fromCharCode cached`, and `join: String.fromCharCode cached`.

Let's break down each approach:

1. **For-loop**: This is a straightforward concatenation using a traditional `for` loop.
2. **String.fromCharCode.apply**: This method applies the `String.fromCharCode` function to each character in the array, which creates a new string object at each iteration.
3. **loop: String cached**: This approach caches the `String` object once and uses it throughout the loop, creating a new string by concatenating characters to the end of the cached string.
4. **loop: String.fromCharCode cached**: Similar to the previous one, but applies the `String.fromCharCode` function directly to the cached `String` object.
5. **join: String.fromCharCode cached**: This approach uses the `Array.join()` method with a custom callback function that creates a new string by concatenating characters using `String.fromCharCode`.

**Pros and Cons**

Here's a brief summary of the pros and cons for each approach:

1. **For-loop**:
	* Pros: Easy to understand, no additional memory allocation required.
	* Cons: May be slower due to repeated function calls and string object creations.
2. **String.fromCharCode.apply**:
	* Pros: Can take advantage of some hardware acceleration (e.g., SIMD instructions).
	* Cons: Creates new string objects at each iteration, leading to higher memory allocation.
3. **loop: String cached**:
	* Pros: Reuses the `String` object, reducing memory allocation and potential performance gains.
	* Cons: May lead to slower startup due to initial string creation.
4. **loop: String.fromCharCode cached**:
	* Similar pros and cons as the previous approach, with an added benefit of avoiding unnecessary function calls.
5. **join: String.fromCharCode cached**:
	* Pros: Reuses the `Array.join()` method, reducing memory allocation and potential performance gains.
	* Cons: May be slower due to additional overhead from the callback function.

**Library and Special Features**

None of these approaches rely on external libraries or special JavaScript features beyond standard JavaScript functions. However, if we consider the general context of this benchmark, it's worth noting that modern browsers may have optimizations or caching mechanisms in place for strings and arrays, which could affect performance.

**Alternatives**

Other alternatives to explore:

* Using `Buffer` objects, which can provide better memory efficiency and potentially faster concatenation.
* Implementing a custom string builder using a linked list or other data structure.
* Utilizing native WebAssembly modules (if available) for optimized string manipulation.
* Considering the use of parallel processing techniques, such as worker threads or web workers, to improve performance.

Keep in mind that these alternatives may require more significant changes to the benchmark setup and implementation.

Related benchmarks:

String from Charcode cached (deg) (version: 0)

Comparing performance of: For-loop vs String.fromCharCode.apply vs loop: String cached vs loop: String.fromCharCode cached vs join: String.fromCharCode cached

Created: 4 months ago by: Guest

Jump to the latest result

For-loop

String.fromCharCode.apply

loop: String cached

loop: String.fromCharCode cached

join: String.fromCharCode cached

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 2 months ago):